Heating apparatus.



1. GOOD.

HEATING APPARATUS.

APPLICATION FILED MAILQ, I916.

Patented. Dec. 18,1917.

2 SHEETS-SHEET l.

1. GOOD.

HEATING APPARATUS.

APPLICATION FILED MAR. 9. 1916.

Patented Dec. 18, 1912'- 2 SHEETS-SHEET 2- W wuewfoz JOHN GOOD, OFBROOKLYN, NEW YORK.

HEATING APPARATUS.

Specification of Letters Batent.

Application filed March 9, 1916. Serial No. 83,033. 4

To all whom it may concern:

Be it known that 1, JOHN G001), a citizen of the United States, residingin Brooklyn, in the county of Kings and State of New York, have inventedthe following described new and useful Improvements in HeatingApparatus. 1

The invention is an improvement in forced draft burner mechanism usingkerosene or heavier oils or liquid fuels, and provides means of highefficiency and extreme simplicity, whereby high temperatures can bedirectly and quickly obtained from the combustion of such heavy fuelswithout preliminary heating of either the fuel or the air andparticularly whereby such heavy fuels can be ignited in their initialcold condition, and whereby also various other advantages and economiesare available over existing means for burning liquid fuels, as will bemade apparent in the description below. The invention further providesmeans whereby said quickly attained high.

temperatures may be produced in a. confined passage entirely closed fromcommunication with the external atmosphere and therefore protectedagainst fire hazard, and

in this latter respect the present invention is an improvement upon myprior application Serial No. 822,813, filed March 6th, 1914, whichattains a like'object. The particular improvement upgn said priorapplication is in the elimination of the high pressure-air for producinga fuel spray which is ignitible in a cold state, that result beingaccomplished according to the present invention by a single source oflow pressure air and a Venturi tube in certain relation thereto and tothe fuel supply, as hereinafter explained. Other objects and advantagesof the invention supplemental toand vindependent of those abovedescribed, "will become apparent to'those skilled in this art from thefollowing description, and the essential structure of the means forproducing such results is pointed out in the claims appended hereto.

The accompanying drawings illustrate several forms of the invention, thepreferred form of the inclosed Figure 1 being to the air type;

Fig. 2 a top plan thereof;

type a simple form of the bpen including Fig. 3 a modificationapplicable to either typ and Fig.4 a longitudinal section of thepreferred inclosed type. I

.In Fig. 1, the reference 1 denotes an ordinary belt-driven fan blower,which is to be understood as representing any suitable supply of air atlow'pressure and in volume appropriate to the requirements of theapparatus. Various types of ainpropelling means are available for usefor this purpose, the suitable pressure being from one quarter of apound to two pounds per square inch, and not necessarily higher than twopounds, The supply of air at this low pressure is conducted by an airpipe 2 to a Venturi tube 3, into which fuel is introduced by a nozzle 4,connected through a needle-valve 6, to a liquid chamber 5, the liquidlevel wherein is somewhat lower than the orifice of the nozzle. TheVenturi tube 3 is designed according to the principles of Venturi-tubedesign well known to the art and with reference to the air, deliveryfrom the blower or source ofair pressure, and so as to create aconsiderable pressure depression at itsthroat or narrowest diameterwithout unduly obstructing the flow of the air through it or building upan undue back pressure in the pipe 2. The nozzle 4 is mounted todischarge into the region'of such pressure depression and preferablydirectly at the throat or narrowest part, where the velocity anddepression are both at their maximum. Discharge of the liquid fuel isaccomplished by the effect of such pressure depresslon, that is to say,as the result of the difference of pressures existing at the throat andupon the surface of the liquid in the chamber 5, which latter pressuremay be atmospheric or otherwise, as desired. In other words, the liquidfuel is sucked through the liquid pipe and nozzle by the relative vacuumin the venturi, and in certain definite proportion to the'amount'of airpassing through the latter, and directly under the control of such airflow. By adjustment of the needlevalve 6, or of the surface pressure inchamber 5, the liquid fuel can be automatically introduced to theVenturi tube in such appropriate and predetermined proportions withreference to the air that the resulting spray or mixture of air andkerosene or other heavy Patented Dec. 18, 1917.

readily accomplished by no greater source of heat than an electriclighted taper. In the open invention shown in Fig. 1, the air necessaryfortthe continued combustion of the ignited Venturi spray may be derivedby contact with the surrounding atmosphere, the general effect andactionafter ignition being somewhat the same as in the familiar blow torch,but with the difierence just noted that the heavy fuel oil is ignitedand burned in spark or by a type form of the an initially cold state andsuffices to producean extremely high temperature immediately upon suchignition. The cold ignition of the relatively non-volatile fuel oils inapparatus constructed as above described, occurs from the cooperatingeffects of the considerable pressure depression and high velocitypeculiar to the Venturi tube, and the relation thereto of the oildelivery, and which I believe myself to be the first to have utilized inthe present relation. The liquid chamber 5 may conveniently be afloat-controlled chamber such as in common use in carbureters forinternal combustion engines, the same being supplied by a pipe 7 fromsome larger 'source of fuel, but any other means of supplying liquidfuel in the necessary proportion and at a substantially constant ratewith reference to the air flow through the Venturi tube, I believe maybe used with equal efiect.

Fig. 3 represents modified by first around the same apparatus leadingthe air; from the blower and in contact with the wall of the Venturitube before admitting it to the entrance end of the latter, the efi'ectbeing to keep the tube cool by contact with the incoming air and to warmsuch air accordingly, before mixing the fuel with it. Manifestly suchadvance heating of the air takes place only after the device has beenstarted inoperation and after the Venturi spray has been ignited cold.

The inclosed type of heating apparatus shown in Fig. 4, comprises an airsource represented as a so called geared blower, marked 8, butequivalent to any suitable means of creating a low pressure supply ofair. This source of air is connected by an air passage 9 to a Venturitube 10, similar in design and purpose to the Venturi tube abovedescribed and supplied with heavy liquid fuel from apparatus of the samedescription and bearing the same reference characters, but the deliveryend of the Venturi tube is disposed within the walls of the casing orstructure in which the tube is mounted, and within which the flame isproduced and confined when the apparatus isin action. Ignition isaccomplished by an electric spark umpingthe gap between the hatc ethook-shaped electrodes 11 of two separate spark plugs 12, mounted in thesame walls and connected to a suitable source of current, not indicatedin the drawing. The spark gap intercepts the blast from the Venturitube, being placed close to the orifice of the latter, and theextremities of the electrodes are turned convergently downward so thatany liquid tending to accumulate thereon, and which might short-circuitthe gap, will be blown back along the respective electrodes, or elsebeblown 0H bodily, thus keeping the gap clear at all times. The sprayissuing from this Venturi tube, as in the form first described, isignitible in a cold state but its proportions give a mixture somewhatricher in fuel than the Venturi tube 3. A single spark is ordinarilysuficient to ignite it, although it is preferred to operate the ignitionmeans continuously when the heating apparatus is called upon only forintermittent service of short duration. For this purpose an ordinarymagneto geared with the blower 8, or an induction coil and batteries, orother equivalent continuous sparking mechanism, is appropriate andsatisfactory. The ignited'spray takes the air needed for its continuedcombustion within the closed and imperforate wall of its inclosure, fromthe supplemental air channel 13, which, however, is supplied from thesame air source as the Venturi tube, all j the airthat does not passthrough the Venturi tube being passed through the supplemental airchannel 13 and desirably so as to join the burning spray uniformly onall sides thereof and just beyond the point of ignition. The damper 14:which controls the relative proportions of the main and supplemental airflows establishes that high velocity of flow through the venturi whichis necessary to create a mixture, ignitible cold at the outlet end, suchhigh velocity being of particular importance in this connection. Whenthe damper is once set it needs no further attention and of course itcould be omitted when the supplemental channel possesses initially theappropriate restriction. Theefi'ect of the damper as just explained issupplemented by forming the burner casing with a further Venturirestriction at or close to the outlet of the Venturi tube 10, so that anauxiliary difierence of pressure is thus created between the two ends ofthe spraying venturi which further augments the velocity through it andenhances the mixture of the spray and air. Substantially completecombustion is established within the closed casing of the apparatus andthe heat thereof is utilized by leading the flame through a relativelynarrow passage which is preferably of such length that only whollyconsumed gases emerge at the ultimate outlet. In the pres ent case, theflame passage,

which may be Said to begin at the ignition point, is constituted by thedivergent end part of the burner caslng, and the annular or bowlshapedspace 16 formed between the exterior surface of the vaporizer plate 17of a hot-plate oil engine, and a wall 18 of heatinsulating materialsurrounding the hot plate. The flame impinges directly upon thevaporizer plate and spreads out uniformly on all sides to an annularchamber 19, around the margin of the plate, whence it escapes from oneor more pipes 20, to a remote discharge, that is to say, to some placewhere the products of combustion can be safely dissipated into theatmosphere. The heating effect is augmented by-the direct impingement ofthe flame and also by making the transfer space 16 relatively thin orshallow, even more so than indicated in Fig. 4, but it will be apparentthat various ways may be resorted to for utilizing the heat ofthe flamewhile confining it within v a closed flame passage out of contact withthe external atmosphere. The walls of the casing which-forms the flamepassage, are imperforate so that the flame therein which is underpressure can escape only through the exhaust, and accidental explosionstherein are safely confined, and the same is also true of the airpassage leading from the air source to the point of ignition; anexplosion is either stifled by the wings of the blower, or with othertypes of air supply harmlessly vented at the intake. Such confinement orinclosure of the air and flame passageshas particular advantage inhot-plate oil engines in that it enables them to be prepared forstarting on their normal working cycle in a minimum time and withoutexposing flame to the engine room. In such case the out-take pipe orpipes 20 are connected to the exhaust pipe of the engine.

In the particular construction of burner casing illustrated in Fig. 4,the Venturi tube 10 is separately formed and held in place inrelationship described, it being observed that the complete inclosure ofthe flame passage and igniting means provides an apparatus in whichcombustion is established and continued, solely by the operation of twooutside agencies, to wit, the air source and the igniter, and that thesemay "be brought into operation by any simple or single mechanism. Inother words, the present invention provides the means whereby theoperator may readily and instantly, as by throwing a handle or lever,start and continue combustion of heavy fuel 'oil in a safely confinedpassage where the heat of its combustion can be utlized for Whateverpurpose required. In this closed form of the heating device, the flamepassage should be of small cross-sectional area from the ignition pointthrough the region in which the heat of the flame is utilized, so thatthe gases moving therethrough shall have continued high velocity andthorough mixing, thereby attaining the highest temperature and bestresults, but the velocity should not be greater at the point of ignitionthan the rate of propagation of flame through the mixture.

I claim:

Heating apparatus comprising a passage connected with a source of airand terminating in a Venturi tube, means for supplying liquid fuel toform in said tube a mixture which ignites in a cold state, and a chamberin said passage surrounding said tube, whereby the heat resulting fromsuch igniticion preheats the air flowing through said tu e. v

In testimony whereof, I have signed this I specificatiom JOHN GOOD.

